c# - What is the fastest way to calculate a Windows folders size?

Question

I need to calculate the size of hundreds of folders, some will be 10MB some maybe 10GB, I need a super fast way of getting the size of each folder using C#.

My end result will hopefully be:

Folder1 10.5GB

Folder2 230MB

Folder3 1.2GB

...

Answer 1

Add a reference to the Microsoft Scripting Runtime and use:

Scripting.FileSystemObject fso = new Scripting.FileSystemObject();
Scripting.Folder folder = fso.GetFolder([folder path]);
Int64 dirSize = (Int64)folder.Size;

If you just need the size, this is much faster than recursing.